罗塞塔号飞船上的 OSIRIS 仪器拍摄的 E 型小行星“司琴”（2867 Steins）图像。

E-type asteroid (2867) Steins as imaged by OSIRIS on board Rosetta.

机构信息

Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany.

出版信息

Science. 2010 Jan 8;327(5962):190-3. doi: 10.1126/science.1179559.

PMID:20056887

Abstract

The European Space Agency's Rosetta mission encountered the main-belt asteroid (2867) Steins while on its way to rendezvous with comet 67P/Churyumov-Gerasimenko. Images taken with the OSIRIS (optical, spectroscopic, and infrared remote( )imaging system) cameras on board Rosetta show that Steins is an oblate body with an effective spherical diameter of 5.3 kilometers. Its surface does not show color variations. The morphology of Steins is dominated by linear faults and a large 2.1-kilometer-diameter crater near its south pole. Crater counts reveal a distinct lack of small craters. Steins is not solid rock but a rubble pile and has a conical appearance that is probably the result of reshaping due to Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) spin-up. The OSIRIS images constitute direct evidence for the YORP effect on a main-belt asteroid.

摘要

欧洲航天局的罗塞塔任务在前往与彗星 67P/楚留莫夫-格拉希门克会合的途中遇到了主带小行星（2867）司琴。罗塞塔号上的 OSIRIS（光学、分光和红外远程成像系统）相机拍摄的图像显示，司琴是一个扁球体，有效球形直径为 5.3 公里。它的表面没有显示颜色变化。司琴的形态主要由线性断层和南极附近一个直径 2.1 公里的大型陨石坑主导。陨石坑计数显示出明显缺乏小陨石坑。司琴不是实心岩石，而是一堆碎石，呈锥形，这可能是由于 Yarkovsky-O'Keefe-Radzievskii-Paddack（YORP）自旋加速导致的重塑。OSIRIS 图像构成了 YORP 效应对主带小行星影响的直接证据。